/*
 * Copyright (c) 2013-2017 ARM Limited. All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the License); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * ----------------------------------------------------------------------
 *
 * $Date:        1. December 2017
 * $Revision:    V2.0.0
 *
 * Project:      CMSIS-DAP Source
 * Title:        SWO.c CMSIS-DAP SWO I/O
 *
 *---------------------------------------------------------------------------*/

#include "DAP_config.h"
#include "DAP.h"

#if (SWO_UART != 0)
#include "Driver_USART.h"
#endif
#if (SWO_STREAM != 0)

#include "cmsis_os2.h"

#endif

#if (SWO_STREAM != 0)
#ifdef DAP_FW_V1
#error "SWO Streaming Trace not supported in DAP V1!"
#endif
#endif

#if (SWO_UART != 0)

#ifndef  SWO_USART_PORT
#define  SWO_USART_PORT 0           /* USART Port Number */
#endif

// USART Driver
#define _USART_Driver_(n)  Driver_USART##n
#define  USART_Driver_(n) _USART_Driver_(n)
extern ARM_DRIVER_USART    USART_Driver_(SWO_USART_PORT);
#define pUSART           (&USART_Driver_(SWO_USART_PORT))

static uint8_t USART_Ready = 0U;

#endif  /* (SWO_UART != 0) */


#if ((SWO_UART != 0) || (SWO_MANCHESTER != 0))


#define SWO_STREAM_TIMEOUT      50U     /* Stream timeout in ms */

#define USB_BLOCK_SIZE          512U    /* USB Block Size */
#define TRACE_BLOCK_SIZE        64U     /* Trace Block Size (2^n: 32...512) */
#ifndef   __WEAK
#if __ICCARM_V8
#define __WEAK __attribute__((weak))
#else
#define __WEAK _Pragma("__weak")
#endif
#endif
// Trace State
static uint8_t TraceTransport = 0U;       /* Trace Transport */
static uint8_t TraceMode = 0U;       /* Trace Mode */
static uint8_t TraceStatus = 0U;       /* Trace Status without Errors */
static uint8_t TraceError[2] = {0U, 0U};  /* Trace Error flags (banked) */
static uint8_t TraceError_n = 0U;       /* Active Trace Error bank */

// Trace Buffer
static uint8_t TraceBuf[SWO_BUFFER_SIZE];  /* Trace Buffer (must be 2^n) */
static volatile uint32_t TraceIndexI = 0U; /* Incoming Trace Index */
static volatile uint32_t TraceIndexO = 0U; /* Outgoing Trace Index */
static volatile uint8_t TraceUpdate;       /* Trace Update Flag */
static uint32_t TraceBlockSize;    /* Current Trace Block Size */

#if (TIMESTAMP_CLOCK != 0U)
// Trace Timestamp
static volatile struct {
    uint32_t index;
    uint32_t tick;
} TraceTimestamp;
#endif

// Trace Helper functions
static void ClearTrace(void);

static void ResumeTrace(void);

static uint32_t GetTraceCount(void);

static uint8_t GetTraceStatus(void);

static void SetTraceError(uint8_t flag);

#if (SWO_STREAM != 0)
extern osThreadId_t SWO_ThreadId;
static volatile uint8_t TransferBusy = 0U; /* Transfer Busy Flag */
static uint32_t TransferSize;      /* Current Transfer Size */
#endif


#if (SWO_UART != 0)

// USART Driver Callback function
//   event: event mask
static void USART_Callback (uint32_t event) {
  uint32_t index_i;
  uint32_t index_o;
  uint32_t count;
  uint32_t num;

  if (event &  ARM_USART_EVENT_RECEIVE_COMPLETE) {
#if (TIMESTAMP_CLOCK != 0U)
    TraceTimestamp.tick = TIMESTAMP_GET();
#endif
    index_o  = TraceIndexO;
    index_i  = TraceIndexI;
    index_i += TraceBlockSize;
    TraceIndexI = index_i;
#if (TIMESTAMP_CLOCK != 0U)
    TraceTimestamp.index = index_i;
#endif
    num   = TRACE_BLOCK_SIZE - (index_i & (TRACE_BLOCK_SIZE - 1U));
    count = index_i - index_o;
    if (count <= (SWO_BUFFER_SIZE - num)) {
      index_i &= SWO_BUFFER_SIZE - 1U;
      TraceBlockSize = num;
      pUSART->Receive(&TraceBuf[index_i], num);
    } else {
      TraceStatus = DAP_SWO_CAPTURE_ACTIVE | DAP_SWO_CAPTURE_PAUSED;
    }
    TraceUpdate = 1U;
#if (SWO_STREAM != 0)
    if (TraceTransport == 2U) {
      if (count >= (USB_BLOCK_SIZE - (index_o & (USB_BLOCK_SIZE - 1U)))) {
        osThreadFlagsSet(SWO_ThreadId, 1U);
      }
    }
#endif
  }
  if (event &  ARM_USART_EVENT_RX_OVERFLOW) {
    SetTraceError(DAP_SWO_BUFFER_OVERRUN);
  }
  if (event & (ARM_USART_EVENT_RX_BREAK         |
               ARM_USART_EVENT_RX_FRAMING_ERROR |
               ARM_USART_EVENT_RX_PARITY_ERROR)) {
    SetTraceError(DAP_SWO_STREAM_ERROR);
  }
}

// Enable or disable UART SWO Mode
//   enable: enable flag
//   return: 1 - Success, 0 - Error
__WEAK uint32_t UART_SWO_Mode (uint32_t enable) {
  int32_t status;

  USART_Ready = 0U;

  if (enable != 0U) {
    status = pUSART->Initialize(USART_Callback);
    if (status != ARM_DRIVER_OK) {
      return (0U);
    }
    status = pUSART->PowerControl(ARM_POWER_FULL);
    if (status != ARM_DRIVER_OK) {
      pUSART->Uninitialize();
      return (0U);
    }
  } else {
    pUSART->Control(ARM_USART_CONTROL_RX, 0U);
    pUSART->Control(ARM_USART_ABORT_RECEIVE, 0U);
    pUSART->PowerControl(ARM_POWER_OFF);
    pUSART->Uninitialize();
  }
  return (1U);
}

// Configure UART SWO Baudrate
//   baudrate: requested baudrate
//   return:   actual baudrate or 0 when not configured
__WEAK uint32_t UART_SWO_Baudrate (uint32_t baudrate) {
  int32_t  status;
  uint32_t index;
  uint32_t num;

  if (baudrate > SWO_UART_MAX_BAUDRATE) {
    baudrate = SWO_UART_MAX_BAUDRATE;
  }

  if (TraceStatus & DAP_SWO_CAPTURE_ACTIVE) {
    pUSART->Control(ARM_USART_CONTROL_RX, 0U);
    if (pUSART->GetStatus().rx_busy) {
      TraceIndexI += pUSART->GetRxCount();
      pUSART->Control(ARM_USART_ABORT_RECEIVE, 0U);
    }
  }

  status = pUSART->Control(ARM_USART_MODE_ASYNCHRONOUS |
                           ARM_USART_DATA_BITS_8       |
                           ARM_USART_PARITY_NONE       |
                           ARM_USART_STOP_BITS_1,
                           baudrate);

  if (status == ARM_DRIVER_OK) {
    USART_Ready = 1U;
  } else {
    USART_Ready = 0U;
    return (0U);
  }

  if (TraceStatus & DAP_SWO_CAPTURE_ACTIVE) {
    if ((TraceStatus & DAP_SWO_CAPTURE_PAUSED) == 0U) {
      index = TraceIndexI & (SWO_BUFFER_SIZE - 1U);
      num = TRACE_BLOCK_SIZE - (index & (TRACE_BLOCK_SIZE - 1U));
      TraceBlockSize = num;
      pUSART->Receive(&TraceBuf[index], num);
    }
    pUSART->Control(ARM_USART_CONTROL_RX, 1U);
  }

  return (baudrate);
}

// Control UART SWO Capture
//   active: active flag
//   return: 1 - Success, 0 - Error
__WEAK uint32_t UART_SWO_Control (uint32_t active) {
  int32_t status;

  if (active) {
    if (!USART_Ready) {
      return (0U);
    }
    TraceBlockSize = 1U;
    status = pUSART->Receive(&TraceBuf[0], 1U);
    if (status != ARM_DRIVER_OK) {
      return (0U);
    }
    status = pUSART->Control(ARM_USART_CONTROL_RX, 1U);
    if (status != ARM_DRIVER_OK) {
      return (0U);
    }
  } else {
    pUSART->Control(ARM_USART_CONTROL_RX, 0U);
    if (pUSART->GetStatus().rx_busy) {
      TraceIndexI += pUSART->GetRxCount();
      pUSART->Control(ARM_USART_ABORT_RECEIVE, 0U);
    }
  }
  return (1U);
}

// Start UART SWO Capture
//   buf: pointer to buffer for capturing
//   num: number of bytes to capture
__WEAK void UART_SWO_Capture (uint8_t *buf, uint32_t num) {
  TraceBlockSize = num;
  pUSART->Receive(buf, num);
}

// Get UART SWO Pending Trace Count
//   return: number of pending trace data bytes
__WEAK uint32_t UART_SWO_GetCount (void) {
  uint32_t count;

  if (pUSART->GetStatus().rx_busy) {
    count = pUSART->GetRxCount();
  } else {
    count = 0U;
  }
  return (count);
}

#endif  /* (SWO_UART != 0) */


#if (SWO_MANCHESTER != 0)

// Enable or disable Manchester SWO Mode
//   enable: enable flag
//   return: 1 - Success, 0 - Error
__WEAK

uint32_t Manchester_SWO_Mode(uint32_t enable) {
    return (0U);
}

// Configure Manchester SWO Baudrate
//   baudrate: requested baudrate
//   return:   actual baudrate or 0 when not configured
__WEAK

uint32_t Manchester_SWO_Baudrate(uint32_t baudrate) {
    return (0U);
}

// Control Manchester SWO Capture
//   active: active flag
//   return: 1 - Success, 0 - Error
__WEAK

uint32_t Manchester_SWO_Control(uint32_t active) {
    return (0U);
}

// Start Manchester SWO Capture
//   buf: pointer to buffer for capturing
//   num: number of bytes to capture
__WEAK

void Manchester_SWO_Capture(uint8_t *buf, uint32_t num) {
}

// Get Manchester SWO Pending Trace Count
//   return: number of pending trace data bytes
__WEAK

uint32_t Manchester_SWO_GetCount(void) {
}

#endif  /* (SWO_MANCHESTER != 0) */


// Clear Trace Errors and Data
static void ClearTrace(void) {

#if (SWO_STREAM != 0)
    if (TraceTransport == 2U) {
        if (TransferBusy != 0U) {
//      SWO_AbortTransfer();
            TransferBusy = 0U;
        }
    }
#endif

    TraceError[0] = 0U;
    TraceError[1] = 0U;
    TraceError_n = 0U;
    TraceIndexI = 0U;
    TraceIndexO = 0U;

#if (TIMESTAMP_CLOCK != 0U)
    TraceTimestamp.index = 0U;
    TraceTimestamp.tick = 0U;
#endif
}

// Resume Trace Capture
static void ResumeTrace(void) {
    uint32_t index_i;
    uint32_t index_o;

    if (TraceStatus == (DAP_SWO_CAPTURE_ACTIVE | DAP_SWO_CAPTURE_PAUSED)) {
        index_i = TraceIndexI;
        index_o = TraceIndexO;
        if ((index_i - index_o) < SWO_BUFFER_SIZE) {
            index_i &= SWO_BUFFER_SIZE - 1U;
            switch (TraceMode) {
#if (SWO_UART != 0)
                case DAP_SWO_UART:
                  TraceStatus = DAP_SWO_CAPTURE_ACTIVE;
                  UART_SWO_Capture(&TraceBuf[index_i], 1U);
                  break;
#endif
#if (SWO_MANCHESTER != 0)
                case DAP_SWO_MANCHESTER:
                    TraceStatus = DAP_SWO_CAPTURE_ACTIVE;
                    Manchester_SWO_Capture(&TraceBuf[index_i], 1U);
                    break;
#endif
                default:
                    break;
            }
        }
    }
}

// Get Trace Count
//   return: number of available data bytes in trace buffer
static uint32_t GetTraceCount(void) {
    uint32_t count;

    if (TraceStatus == DAP_SWO_CAPTURE_ACTIVE) {
        do {
            TraceUpdate = 0U;
            count = TraceIndexI - TraceIndexO;
            switch (TraceMode) {
#if (SWO_UART != 0)
                case DAP_SWO_UART:
                  count += UART_SWO_GetCount();
                  break;
#endif
#if (SWO_MANCHESTER != 0)
                case DAP_SWO_MANCHESTER:
                    count += Manchester_SWO_GetCount();
                    break;
#endif
                default:
                    break;
            }
        } while (TraceUpdate != 0U);
    } else {
        count = TraceIndexI - TraceIndexO;
    }

    return (count);
}

// Get Trace Status (clear Error flags)
//   return: Trace Status (Active flag and Error flags)
static uint8_t GetTraceStatus(void) {
    uint8_t status;
    uint32_t n;

    n = TraceError_n;
    TraceError_n ^= 1U;
    status = TraceStatus | TraceError[n];
    TraceError[n] = 0U;

    return (status);
}

// Set Trace Error flag(s)
//   flag:  error flag(s) to set
static void SetTraceError(uint8_t flag) {
    TraceError[TraceError_n] |= flag;
}


// Process SWO Transport command and prepare response
//   request:  pointer to request data
//   response: pointer to response data
//   return:   number of bytes in response (lower 16 bits)
//             number of bytes in request (upper 16 bits)
uint32_t SWO_Transport(const uint8_t *request, uint8_t *response) {
    uint8_t transport;
    uint32_t result;

    if ((TraceStatus & DAP_SWO_CAPTURE_ACTIVE) == 0U) {
        transport = *request;
        switch (transport) {
            case 0U:
            case 1U:
#if (SWO_STREAM != 0)
            case 2U:
#endif
                TraceTransport = transport;
                result = 1U;
                break;
            default:
                result = 0U;
                break;
        }
    } else {
        result = 0U;
    }

    if (result != 0U) {
        *response = DAP_OK;
    } else {
        *response = DAP_ERROR;
    }

    return ((1U << 16) | 1U);
}


// Process SWO Mode command and prepare response
//   request:  pointer to request data
//   response: pointer to response data
//   return:   number of bytes in response (lower 16 bits)
//             number of bytes in request (upper 16 bits)
uint32_t SWO_Mode(const uint8_t *request, uint8_t *response) {
    uint8_t mode;
    uint32_t result;

    mode = *request;

    switch (TraceMode) {
#if (SWO_UART != 0)
        case DAP_SWO_UART:
          UART_SWO_Mode(0U);
          break;
#endif
#if (SWO_MANCHESTER != 0)
        case DAP_SWO_MANCHESTER:
            Manchester_SWO_Mode(0U);
            break;
#endif
        default:
            break;
    }

    switch (mode) {
        case DAP_SWO_OFF:
            result = 1U;
            break;
#if (SWO_UART != 0)
            case DAP_SWO_UART:
              result = UART_SWO_Mode(1U);
              break;
#endif
#if (SWO_MANCHESTER != 0)
        case DAP_SWO_MANCHESTER:
            result = Manchester_SWO_Mode(1U);
            break;
#endif
        default:
            result = 0U;
            break;
    }
    if (result != 0U) {
        TraceMode = mode;
    } else {
        TraceMode = DAP_SWO_OFF;
    }

    TraceStatus = 0U;

    if (result != 0U) {
        *response = DAP_OK;
    } else {
        *response = DAP_ERROR;
    }

    return ((1U << 16) | 1U);
}


// Process SWO Baudrate command and prepare response
//   request:  pointer to request data
//   response: pointer to response data
//   return:   number of bytes in response (lower 16 bits)
//             number of bytes in request (upper 16 bits)
uint32_t SWO_Baudrate(const uint8_t *request, uint8_t *response) {
    uint32_t baudrate;

    baudrate = (uint32_t) (*(request + 0) << 0) |
               (uint32_t) (*(request + 1) << 8) |
               (uint32_t) (*(request + 2) << 16) |
               (uint32_t) (*(request + 3) << 24);

    switch (TraceMode) {
#if (SWO_UART != 0)
        case DAP_SWO_UART:
          baudrate = UART_SWO_Baudrate(baudrate);
          break;
#endif
#if (SWO_MANCHESTER != 0)
        case DAP_SWO_MANCHESTER:
            baudrate = Manchester_SWO_Baudrate(baudrate);
            break;
#endif
        default:
            baudrate = 0U;
            break;
    }

    if (baudrate == 0U) {
        TraceStatus = 0U;
    }

    *response++ = (uint8_t) (baudrate >> 0);
    *response++ = (uint8_t) (baudrate >> 8);
    *response++ = (uint8_t) (baudrate >> 16);
    *response = (uint8_t) (baudrate >> 24);

    return ((4U << 16) | 4U);
}


// Process SWO Control command and prepare response
//   request:  pointer to request data
//   response: pointer to response data
//   return:   number of bytes in response (lower 16 bits)
//             number of bytes in request (upper 16 bits)
uint32_t SWO_Control(const uint8_t *request, uint8_t *response) {
    uint8_t active;
    uint32_t result;

    active = *request & DAP_SWO_CAPTURE_ACTIVE;

    if (active != (TraceStatus & DAP_SWO_CAPTURE_ACTIVE)) {
        if (active) {
            ClearTrace();
        }
        switch (TraceMode) {
#if (SWO_UART != 0)
            case DAP_SWO_UART:
              result = UART_SWO_Control(active);
              break;
#endif
#if (SWO_MANCHESTER != 0)
            case DAP_SWO_MANCHESTER:
                result = Manchester_SWO_Control(active);
                break;
#endif
            default:
                result = 0U;
                break;
        }
        if (result != 0U) {
            TraceStatus = active;
#if (SWO_STREAM != 0)
            if (TraceTransport == 2U) {
                osThreadFlagsSet(SWO_ThreadId, 1U);
            }
#endif
        }
    } else {
        result = 1U;
    }

    if (result != 0U) {
        *response = DAP_OK;
    } else {
        *response = DAP_ERROR;
    }

    return ((1U << 16) | 1U);
}


// Process SWO Status command and prepare response
//   response: pointer to response data
//   return:   number of bytes in response
uint32_t SWO_Status(uint8_t *response) {
    uint8_t status;
    uint32_t count;

    status = GetTraceStatus();
    count = GetTraceCount();

    *response++ = status;
    *response++ = (uint8_t) (count >> 0);
    *response++ = (uint8_t) (count >> 8);
    *response++ = (uint8_t) (count >> 16);
    *response = (uint8_t) (count >> 24);

    return (5U);
}


// Process SWO Extended Status command and prepare response
//   request:  pointer to request data
//   response: pointer to response data
//   return:   number of bytes in response (lower 16 bits)
//             number of bytes in request (upper 16 bits)
uint32_t SWO_ExtendedStatus(const uint8_t *request, uint8_t *response) {
    uint8_t cmd;
    uint8_t status;
    uint32_t count;
#if (TIMESTAMP_CLOCK != 0U)
    uint32_t index;
    uint32_t tick;
#endif
    uint32_t num;

    num = 0U;
    cmd = *request;

    if (cmd & 0x01U) {
        status = GetTraceStatus();
        *response++ = status;
        num += 1U;
    }

    if (cmd & 0x02U) {
        count = GetTraceCount();
        *response++ = (uint8_t) (count >> 0);
        *response++ = (uint8_t) (count >> 8);
        *response++ = (uint8_t) (count >> 16);
        *response++ = (uint8_t) (count >> 24);
        num += 4U;
    }

#if (TIMESTAMP_CLOCK != 0U)
    if (cmd & 0x04U) {
        do {
            TraceUpdate = 0U;
            index = TraceTimestamp.index;
            tick = TraceTimestamp.tick;
        } while (TraceUpdate != 0U);
        *response++ = (uint8_t) (index >> 0);
        *response++ = (uint8_t) (index >> 8);
        *response++ = (uint8_t) (index >> 16);
        *response++ = (uint8_t) (index >> 24);
        *response++ = (uint8_t) (tick >> 0);
        *response++ = (uint8_t) (tick >> 8);
        *response++ = (uint8_t) (tick >> 16);
        *response++ = (uint8_t) (tick >> 24);
        num += 4U;
    }
#endif

    return ((1U << 16) | num);
}


// Process SWO Data command and prepare response
//   request:  pointer to request data
//   response: pointer to response data
//   return:   number of bytes in response (lower 16 bits)
//             number of bytes in request (upper 16 bits)
uint32_t SWO_Data(const uint8_t *request, uint8_t *response) {
    uint8_t status;
    uint32_t count;
    uint32_t index;
    uint32_t n, i;

    status = GetTraceStatus();
    count = GetTraceCount();

    if (TraceTransport == 1U) {
        n = (uint32_t) (*(request + 0) << 0) |
            (uint32_t) (*(request + 1) << 8);
        if (n > (DAP_PACKET_SIZE - 4U)) {
            n = DAP_PACKET_SIZE - 4U;
        }
        if (count > n) {
            count = n;
        }
    } else {
        count = 0U;
    }

    *response++ = status;
    *response++ = (uint8_t) (count >> 0);
    *response++ = (uint8_t) (count >> 8);

    if (TraceTransport == 1U) {
        index = TraceIndexO;
        for (i = index, n = count; n; n--) {
            i &= SWO_BUFFER_SIZE - 1U;
            *response++ = TraceBuf[i++];
        }
        TraceIndexO = index + count;
        ResumeTrace();
    }

    return ((2U << 16) | (3U + count));
}


#if (SWO_STREAM != 0)

// SWO Data Transfer complete callback
void SWO_TransferComplete(void) {
    TraceIndexO += TransferSize;
    TransferBusy = 0U;
    ResumeTrace();
    osThreadFlagsSet(SWO_ThreadId, 1U);
}

// SWO Thread
__NO_RETURN void SWO_Thread(void *argument) {
    uint32_t timeout;
    uint32_t flags;
    uint32_t count;
    uint32_t index;
    uint32_t i, n;
    (void) argument;

    timeout = osWaitForever;

    for (;;) {
        flags = osThreadFlagsWait(1U, osFlagsWaitAny, timeout);
        if (TraceStatus & DAP_SWO_CAPTURE_ACTIVE) {
            timeout = SWO_STREAM_TIMEOUT;
        } else {
            timeout = osWaitForever;
            flags = osFlagsErrorTimeout;
        }
        if (TransferBusy == 0U) {
            count = GetTraceCount();
            if (count != 0U) {
                index = TraceIndexO & (SWO_BUFFER_SIZE - 1U);
                n = SWO_BUFFER_SIZE - index;
                if (count > n) {
                    count = n;
                }
                if (flags != osFlagsErrorTimeout) {
                    i = index & (USB_BLOCK_SIZE - 1U);
                    if (i == 0U) {
                        count &= ~(USB_BLOCK_SIZE - 1U);
                    } else {
                        n = USB_BLOCK_SIZE - i;
                        if (count >= n) {
                            count = n;
                        } else {
                            count = 0U;
                        }
                    }
                }
                if (count != 0U) {
                    TransferSize = count;
                    TransferBusy = 1U;
                    SWO_QueueTransfer(&TraceBuf[index], count);
                }
            }
        }
    }
}

#endif  /* (SWO_STREAM != 0) */


#endif  /* ((SWO_UART != 0) || (SWO_MANCHESTER != 0)) */
